Hi,
My parents are here on a US visit for the first time on March21' 2018 & have I94 till Sept 16'2018. We need them to be here from December 2018 to May 2019 as we are expecting a baby in December. Would there be any problem at the POE if they go back at the end of July and come back at the beginning of December? Or it is better to apply for an extension?